It’s the world’s biggest marketplace, home to 181m wheelers and dealers and probably the best place to buy or sell anything — from vintage cars and unwanted gifts to Britney Spears’s hair, which was recently offered on the site for $1m.

Online auctioning is so simple that anyone can do it and we Brits are eBay’s most enthusiastic users: we trade about £50 per head per year. However, if you want to find the best deals or the best price for your goods you need a little savvy.

Fortunately the web can help. Alongside tutorials on how to sell your items you can find services that will help you make the winning bid. It’s also crucial to know that eBay is far from the only game in town; there are a host of other online auctions for bargain hunters.

BUYING ON EBAY

New visitors are drawn to eBay by the prospect of snapping up a bargain, but it can be a long process to find what you want because of the site’s size. Tell the free AuctionSieve program, available from www.auctionsieve.com, what you want and it will scour eBay in a far more comprehensive manner than the site’s own search facility. It will also remain on in the background while you do other things and stay alert for bargains you are interested in.

EBay is an English teacher’s nightmare. The spelling is so bad that desirable goods are often hidden from a search. Sites such as fatfingers.co.uk or www.lowcostbid.com are designed to decipher the mistakes for you. Type the item you are looking for into the site’s search engine and it will bring up everything on eBay that contains a variation of that spelling (“playstaion” for “PlayStation” for instance).

The next challenge is making a successful bid. There are said to be nine buyers for every seller on eBay, which means there’s always competition for the best picks. A helping hand can therefore be useful.

In order to ensure that nobody gazumps you and makes a higher bid for an item, you can install a so-called “sniping” program on your computer. This will monitor your bids and make sure yours is the highest when the auction ends. You can find a comparison of sniping software at www.auctionbytes.com, some of which are free.

SELLING ON EBAY

EBay’s own discussion boards are the chief source of information on how best to sell your possessions. Here patient contributors answer questions such as, “I want to start an eBay business but I don’t know what to sell”. Answer: sell something you are interested in, add a 40-50% mark-up on the wholesale price and expect to clear a 10% profit after expenses such as payments to eBay and postage and packaging.

So-called PowerSellers are at the top of the food chain. These are defined as people who shift £750 worth of business or 100 items a month, and have a 98% or higher positive feedback rating (after each transaction buyers are encouraged to rate how good your performance as a seller was). Being one means people are more likely to trust you.

If you are selling common items, then you’ll need an idea of the going rate so you can set a realistic reserve price (the lowest price at which you are willing to sell your item). Try searching finished auctions (called “completed listings”) to see what certain goods normally go for.

It’s almost always best to begin with a low starting price to entice bidders, according to research by the London Business School (summarised at www.london.edu/facultyresearch754.html) and set a reserve to make sure it’s not sold too cheaply.

Selling can be a fiddly time-consuming nuisance. If you don’t know a geeky teenager whose arm you can twist to do it, www.Auctioning4u.co.uk is a much publicised eBay facilitator, which will make a professional job of selling your junk. For an extra £20-£40 it will even come and collect it and, unlike most auction sites, it is contactable by phone. But it takes a 30% commission.

EBay virgins can attend a one-day course to improve their selling skills. Run by eBay’s own staff, these seminars are held nationwide and cost £49 (pages.ebay.co.uk/university).

ALTERNATIVES TO EBAY

EBay did not get where it is today by offering fantastic customer service. On the contrary, it’s known as greedbay and ebad to its detractors. Fortunately, it is not the only wielder of a virtual hammer. In terms of items for sale, www.cqout.com claims to be the UK’s second largest online marketplace. Simpler and cheaper than eBay, it aims to keep out dodgy dealers with a “three strikes and you’re out” policy on negative feedback.

If you’re keen to trade with like-minded collectors or belong to a collecting club www.specialistauctions.com is an elegant site auctioning the likes of sports memorabilia, meterorites and stamps. Each has a moderator or expert to help in the event of suspected fakes.

The police offer an online auction of the lost and found at www.bumblebeeauctions.co.uk. Bargain hunters should head to www.lastminute-auction.com/uk, which searches for auctions where the bid is £1 or less with under an hour to go.

A DIFFERENT APPROACH

Launched in February, www.humraz.com is a property auction site with a catchy concept: it sells houses to the lowest unique bid. This could be anything from 1p to a maximum 5% of the market value (that’s £9,000 for the house it is currently selling). The site charges £3 for online or SMS bids, and will indicate roughly where the bidding has got to. But as there are 100 price points in every pound, buying here is a gamble that will probably need a sizeable budget.

You can find a host of police auctions at www.police-information. co.uk, while www.ganews.co.uk provides a list of all government auctions to subscribers for £59.50pa.

Christie’s doesn’t auction online, but its live service does the next best thing by letting you watch, hear and bid in a Christie’s saleroom auction from your computer screen via a webcam. Sign up at tinyurl.com/2hg2d2

KNOW YOUR RIGHTS

Fraud is the biggest fear and Citizens Advice (www.citizensadvice.org.uk ) has horror stories, such as how a £6,000 car bought at auction needed £3,000 worth of repairs. Its sister site www.adviceguide.org.uk sets out your rights and how to report fraud, but as www.euroconsumer.org.uk explains, when buying from a private individual rights are limited. You can’t complain if the goods are not fit for purpose, nor can you cancel the order.

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